Here is the full list of all 68 Tannenberg achievements. It takes around 15-20 hours to unlock all of the achievements on Windows.
Call in Artillery or Recon from a sector.
Club someone to death with binoculars.
Unlock all specializations for the K.u.K. Trupp.
Get 10 kills with swords.
Issue 10 command orders.
Kill an enemy soldier manning a heavy machine gun with a head shot.
Kill 3 people with a sabre in an enemy held capture zone.
Capture 10 enemy sectors.
Resupply your ammo.
Die 10 seconds after spawning.
Complete a match on a foggy map.
Make a successful retreat
Used voice chat.
Have a look at the overview map.
Kill 4+ enemies in a capture zone.
Get 7 squad spawns on a single life as NCO.
Kill an enemy while shooting through an object.
Kill 10 people with a heavy machine gun in a single life.
Kick a bot off of a heavy machine gun.
Damage two enemies with one bullet.
Get a kill while injured.
Kill 5 NCO's in a match.
Make 5 kills within the first two minutes of the match.
Shoot an enemy while being suppressed or shaken by artillery.
In a single life, take damage from melee attacks and gun shots from a player or players, before being killed by someone entirely different.
Unlock all specializations for the Frontovik.
Unlock all specializations for the Cossacks.
Unlock all specializations for the Infanterie.
Cut off at least 3 enemy sectors.
Win 10 games as the Central Powers.
Win 10 matches as the Entente Powers.
Be part of the top scoring squad in a match.
Playing as the Entente Powers, capture the enemy HQ.
Playing as the Central Powers, capture the enemy HQ.
Get the first kill in a match.
Playing as the K.u.K, lose a battle in the Carpathians.
Complete a match on a night map.
Complete a match on a snowy map.
Get a kill from 150m.
Check out the credits screen.
Used voice commands 50 times.
Die from falling down.
Have your entire squad agree on a vote to change the squad name or type.
Switch to other team when asked for autobalance.
Chop off someone's limbs with a sword.
Perform a role switch.
Fight in every weather condition.
Get killed by your own grenade.
Start a private match.
Exhaust all your revolver ammo without missing a shot.
Using a sword, kill an opponent who is also using a sword.
Kill 4 enemies with a single grenade or call in.
Kill 25 enemies with artillery as the Entente Powers.
Kill 25 enemies with artillery as the Central Powers.
Win a game with a points difference of 100 or less.
Get killed by bots 50 times.
Win 25 Gold Medals.
As Frontovik, while crouched, get 3 grenade kills.
Get 50 artillery kills using trench phones.
Visit every sector in a Maneuver match.
Capture an enemy sector alongside 10 or more other people.
Be the first to get killed by an enemy in a game.
Become cut-off in a sector.
Playing as the Infanterie, win a battle in East Prussia.
Kill 25 enemies with a HMG.
Unlock all specializations for the Roumanians
Unlock all specializations for the Bulgarians
Unlock all specializations for the Latvians.